While exploring different avenues for future con-ed fulfillment, I stumbled onto a very RECENT research commentary by Karla Franck FAAOMPT in regards to comparing open chain and closed chain exercises post ACL reconstruction. She sums up her article with the following important take home messages:
1) Both open kinetic chain (OKC) and closed kinetic chain (CKC) exercises can produce similar stress on the ACL, so PTs must make sure to have consideration for:
a. the surgeons protocol
b. the degree of knee motion and position in range
c. loads applied depending on stage of healing and patient abilities
2) OKC isometric quadriceps contraction from 0-45 degrees of flexion and active knee flexion-extension from 0-50 degrees produce the greatest strain on the ACL.
3) OKC exercise in the ranges of 60-90 degrees of flexion produce no strain on the ACL and are therefore safe on the healing graft.
4) CKC exercise attenuates an increasing external resistance unlike OKC exercise, and therefore can be potentially safer for the healing graft when performing loaded exercise.
5) CKC exercises are more effective at restoring normal knee function with regard to strength and range of motion, and can often reduce pain and enhance knee proprioception. As such, CKC exercises need to be a vital part of a patient’s knee rehabilitation.
The article summary is a great review and some justification for those looking to mix both open and closed chain exercises during ACL reconstruction rehab.